CVE-2026-48777: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in gtsteffaniak filebrowser
CVE-2026-48777 is a critical path traversal vulnerability in the gtsteffaniak filebrowser web-based file manager. Versions prior to 1.3.3-stable and 1.4.2-beta are affected. The vulnerability exists in the publicPatchHandler, where user-supplied paths are joined with a trusted base path before sanitization, allowing traversal outside the intended directory. Exploitation requires a public share link with modification permissions, enabling an attacker to move, copy, or rename arbitrary files within the share owner's root directory. This issue was fixed in versions 1.3.3-stable and 1.4.2-beta.
AI Analysis
Technical Summary
FileBrowser Quantum versions before 1.3.3-stable and 1.4.2-beta contain a path traversal vulnerability (CWE-22) in the publicPatchHandler endpoint. The handler joins user-controlled fromPath and toPath fields with a trusted directory path using filepath.Join, which collapses '..' segments before the sanitizer runs. Consequently, the sanitizer does not detect traversal attempts, allowing file operations outside the shared directory. This vulnerability is exploitable by anyone with a public share link that has AllowModify=true permissions. The flaw is similar to a previously patched issue (CVE-2026-44542) but was not fixed in the PATCH handler until these versions.
Potential Impact
An attacker with a public share link that allows modifications can exploit this vulnerability to move, copy, or rename arbitrary files outside the intended shared directory within the share owner's source root. This can lead to unauthorized file manipulation, potentially compromising data integrity and confidentiality within the affected file system scope.
Mitigation Recommendations
This vulnerability has been fixed in FileBrowser Quantum versions 1.3.3-stable and 1.4.2-beta. Users should upgrade to these or later versions to remediate the issue. No other mitigation or temporary workaround is indicated by the vendor advisory.
CVE-2026-48777: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in gtsteffaniak filebrowser
Description
CVE-2026-48777 is a critical path traversal vulnerability in the gtsteffaniak filebrowser web-based file manager. Versions prior to 1.3.3-stable and 1.4.2-beta are affected. The vulnerability exists in the publicPatchHandler, where user-supplied paths are joined with a trusted base path before sanitization, allowing traversal outside the intended directory. Exploitation requires a public share link with modification permissions, enabling an attacker to move, copy, or rename arbitrary files within the share owner's root directory. This issue was fixed in versions 1.3.3-stable and 1.4.2-beta.
CVSS v4.0
Score 9.3critical
Affected software
pkg:github/gtsteffaniak/filebrowserRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
FileBrowser Quantum versions before 1.3.3-stable and 1.4.2-beta contain a path traversal vulnerability (CWE-22) in the publicPatchHandler endpoint. The handler joins user-controlled fromPath and toPath fields with a trusted directory path using filepath.Join, which collapses '..' segments before the sanitizer runs. Consequently, the sanitizer does not detect traversal attempts, allowing file operations outside the shared directory. This vulnerability is exploitable by anyone with a public share link that has AllowModify=true permissions. The flaw is similar to a previously patched issue (CVE-2026-44542) but was not fixed in the PATCH handler until these versions.
Potential Impact
An attacker with a public share link that allows modifications can exploit this vulnerability to move, copy, or rename arbitrary files outside the intended shared directory within the share owner's source root. This can lead to unauthorized file manipulation, potentially compromising data integrity and confidentiality within the affected file system scope.
Mitigation Recommendations
This vulnerability has been fixed in FileBrowser Quantum versions 1.3.3-stable and 1.4.2-beta. Users should upgrade to these or later versions to remediate the issue. No other mitigation or temporary workaround is indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-22T20:18:20.364Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a31a4690b89be68881528ed
Added to database: 6/16/2026, 7:30:49 PM
Last enriched: 6/16/2026, 7:45:07 PM
Last updated: 6/16/2026, 8:41:29 PM
Views: 3
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.